This invention relates to headliner panels for lining the interior surface of an automotive roof and more particularly to a self-supporting paper composite headliner panel.
The interior surface of an automobile roof is commonly covered or lined with a material which presents an attractive appearance and also acts as a sound absorber. Molded fiber glass panels and foam liners are examples of such liners. Basically, these products adequately perform the functions for which they were designed. However, they are too expensive to be used in economy vehicles. Economy vehicles require a liner that is not only attractive and sound absorbing, but one which is less costly.
One of the materials designers consider when confronted with the need to produce an inexpensive shaped product such as an automotive headliner is wood fibers. Wood fibers are readily available, inexpensive and can be formed into various shapes by a variety of manufacturing techniques. Hardboard headliners have been manufactured from a wood fiber mat formed from an aqueous slurry. The wood fiber mat is placed in a mold where resins in the wood fiber mat enable the mat to be compressed to a higher density and shaped under heat and pressure. However, this product is too heavy; it is difficult to mold; and it has poor acoustical properties.
Other attempts to produce light, low cost headliners have involved forming the headliners from two paperboard facers with a corrugated paperboard medium sandwiched between the paperboard facers. While inexpensive, these headliners lack adequate sound absorption properties and are difficult to form, without cracking, into the dished shape required for a headliner.
U.S. Pat. Nos. 4,886,696 and 5,057,176, disclose a corrugated paperboard automotive headliner which solves many of the problems associated with the previously discussed headliners. The headliner disclosed in these patents is self-supporting, inexpensive and exhibits surprisingly good sound absorption properties. While the headliner of the '696 and the '176 patents performs very well, the self-supporting, light weight headliner of the present invention is inexpensive and provides another approach to solving the headliner problems associated with economy vehicles.